The actor has shed his usually muscular body for a new film role in "The Dallas Buyer's Club," which tells the real-life story of Ron Woodruff, a drug addict in 1980s-era Texas who contracts HIV. Woodruff became one of the first AIDS activists and launched one of the first AIDS support groups.

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In August, McConaughey told Us Weekly he was eating "small amounts" of high-protein, low-carb good to lose weight for the role. "I'll get down to the weight I need to get to," he said. "I'm on my way, and it's what I need to do for the job."

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"I'm playing a guy who was sick and would have loved to have been healthier but wasn't," McConaughey explained. "For me, it's more of a mental thing than a physical thing."